My family bought a plot in Rajasthan back in 1989. We received the patta in 1992, but then in 1996, the SDM issued a different patta for the same plot. Should we consider taking legal action against the government? Is it possible to file a lawsuit in this situation?

Yes, you can consider legal action as the issuance of two pattas for the same plot raises concerns about the validity of the later patta and potential ownership disputes. You can file a lawsuit in the relevant court in Rajasthan to challenge the second patta and seek rightful ownership based on the first patta and supporting documents.